Optimal shape design of dielectric structure using FDTD and topology optimization

In this paper, an optimal design method based on the FDTD technique and the topology optimization is proposed. Topology Optimization is a scheme to search an optimal shape by adjusting the material properties of design space. And by introducing the adjoint variable method, we can effectively estimate a derivative of objective function with respect to design variable. In order to verify our method, a shape design problem of dielectric structure is tested in the TM^z case. In this example, the permittivity density at each grid is taken as design variable.